Method for trains to establish virtual coupling operation mode

ABSTRACT

A method for trains to establish a virtual coupling (VC) operation mode, which includes: successively determining whether adjacent preceding and following trains on a same line meet initial conditions and formation conditions of the VC; and performing VC on both trains meeting the initial conditions and formation conditions, and determining the VC of all trains on the line through the above determination method to obtain an overall VC. The method further including controlling operation of a leading train in the overall VC according to driving permission of the VC, and controlling operation of each of remaining following trains based on communication with the corresponding adjacent preceding train in combination with the following train&#39;s own driving information. An establishment process of forming a VC operation mode, thereby improving efficiency of train transportation and flexibility of organization and scheduling.

This patent application claims the benefit and priority of Chinese Patent Application No. 202210346971.6, entitled “METHOD FOR TRAINS TO ESTABLISH VIRTUAL COUPLING OPERATION MODE” filed on Apr. 1, 2022, the disclosure of which is incorporated by reference herein in its entirety as part of the present application.

BACKGROUND OF THE INVENTION Technical Field

The present disclosure relates to the technical field of rail transit, and in particular, to a method for trains to establish a virtual coupling (VC) operation mode.

Background Art

VC is a new concept of train operation control that multiple trains are coupled to form a coupled fleet, in such way, trains can be coupled and decoupled dynamically during operation, which may adapt to specific transportation needs, shorten train operation intervals, improve train operation efficiency, and achieve zero waste of transportation capacity.

At present, VC is in the stage of exploration and research, including feasibility, transportation capacity advantages, and methods for controlling the coupled fleet. It is believed that there are no specific technical solutions and application cases in China. Therefore, there is an urgent need for a specific technical solution established based on a second VC, which specifies process and conditions for formation of coupling, and provides technical support for establishment and application of a VC system.

SUMMARY

An objective of the present disclosure intends to provide a method for trains to establish a VC operation mode, which specifies an establishment process of forming a second VC operation mode, thereby improving efficiency of train transportation and flexibility of organization and scheduling.

In order to achieve the above objective, the present disclosure provides the following technical solutions:

The method for the trains to establish the VC operation mode includes:

-   -   controlling, by vehicle on-board controllers (VOBCs),         corresponding trains on a same line meeting initial conditions         of the VC to form an initial coupling, where initial states of         all the trains are a stable platform stop status;     -   determining, by a zone controller (ZC), whether each train in         the initial coupling meets formation conditions of the VC         according to first coupling train IDs and a first coupling         sequence in the initial coupling;     -   if yes, controlling, by VOBCs meeting the formation conditions         of the VC, corresponding trains to form an overall VC;     -   calculating, by the ZC, driving permission of the VC according         to line engineering data, an incoming route state of the overall         VC, and a position of a leading train in the overall VC, where         the incoming route state includes an incoming route locking         state and an incoming route unlocking state;     -   controlling. by a VOBC of the leading train, operation of the         leading train according to the driving permission of the VC,         where each following train in the overall VC is communicatively         connected with an adjacent preceding train; and     -   controlling, by a VOBC of each following train, operation of the         corresponding following train according to each following         train's own driving information and driving information of the         adjacent preceding train, where each following train's own         driving information includes each following train's own driving         speed and each following train's own driving position, and the         driving information of the adjacent preceding train includes a         speed and position of the adjacent preceding train.

According to the specific embodiments provided by the present disclosure, the present disclosure discloses the following technical effects:

The present disclosure provides a method for trains to establish a VC operation mode. The method includes: successively determining whether adjacent preceding and following trains on a same line meet initial conditions and formation conditions of the VC; performing VC on preceding and following trains both meeting the initial conditions and formation conditions of the VC, and determining the VC of all trains on the line through the above determination method to finally obtain an overall VC; and controlling operation of a leading train in the overall VC according to driving permission of the VC, and controlling operation of each of remaining following trains based on communication with the corresponding adjacent preceding train in combination with the following train's own driving information. According to the above steps, the present disclosure proposes an establishment process of forming a VC operation mode, thereby improving efficiency of train transportation and flexibility of organization and scheduling, and providing technical support for establishment and application of the VC system.

BRIEF DESCRIPTION OF THE DRAWINGS

To describe the technical solutions in the embodiments of the present disclosure or in the prior art more clearly, the accompanying drawings required for the embodiments are briefly described below. Apparently, the accompanying drawings in the following description show merely some embodiments of the present disclosure, and those of ordinary skill in the art may still derive other accompanying drawings from these accompanying drawings without creative efforts.

FIG. 1 is a schematic diagram of an operation mode of hitting a hard wall and an operation mode of hitting a soft wall in Embodiment 1 of the present disclosure;

FIG. 2 is a flowchart of a method for trains to establish a VC operation mode provided by Embodiment 1 of the present disclosure; and

FIG. 3 is a sequence diagram of a method for trains to establish a VC operation mode provided by Embodiment 1 of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The technical solutions of the embodiments of the present disclosure are clearly and completely described below with reference to the accompanying drawings. Apparently, the described embodiments are merely a part rather than all of the embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.

An objective of the present disclosure intends to provide a method for trains to establish a VC operation mode, which specifies an establishment process of forming a VC operation mode, thereby improving efficiency of train transportation and flexibility of organization and scheduling.

To make the above-mentioned objective, features, and advantages of the present disclosure clearer and more comprehensible, the present disclosure will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Embodiment 1

The process how trains are coupled is an important issue of VC. In order to improve efficiency of train transportation and flexibility of organization and scheduling, the present embodiment provides a method for trains to establish a VC operation mode on the basis of the existing physical coupler coupling mode of the train control system, which proposes an establishment process of forming a VC operation mode, including initial conditions to be met for forming the VC and functional requirements and information interaction content and sequential logic of the automatic train supervision (AITS) system, the ZC, the VOBC, the VC plan management (VCPM) subsystem, and the computer-based interlocking (131) device. The method for the trains to establish the VC operation mode specifically includes the following.

Design principles and basic assumptions:

(1) Before the VC is formed, the train operates in a fully automatic operation mode.

(2) The system architecture is designed in accordance with fully automatic operation. The ATS system, the ZC, and the VOBC all save an electronic database during operation. The electronic database contains configuration information, such as IDs and IPs of all devices. The information is globally unique and remains unchanged during operation. The versions of the electronic database for all systems are consistent, which can be guaranteed by functions such as database design and version comparison.

(3) Before the VC is formed, the trains operate in a mode of hitting a hard wall, and after the VC is formed, the trains operate in a mode of hitting a soft wall. FIG. 1 shows the operation modes of hitting the hard wall and hitting the soft wall. The mode of hitting the hard wall refers to an operation mode in which a following train takes a rear of a preceding train as an end point of driving permission when the following train is tracking the preceding train. The mode assumes that the preceding train hits a “hard wall”, causing an instant stop. The mode of hitting the soft wall refers to an operation mode in which the following train takes an emergency braking distance position of the preceding train as an end point of the driving permission when the following train is tracking the preceding train. The mode assumes that the preceding train hits a “soft wall” and slows down to stop. When hitting the hard wall, the end point of the driving permission for the following train does not consider the dynamics of the preceding train. When hitting the soft wall, the end point of the driving permission for the following train needs to consider the dynamics of the preceding train, and can cross the current position of the preceding train.

FIG. 2 shows a flowchart of specific steps of a method for trains to establish a VC operation mode, including steps S1-S6.

S1: Each VOBC controls a corresponding train in an operation state to drive into the same platform for stop. FIG. 3 shows a sequence diagram of a method for trains to establish a VC operation mode, specifically including the following.

For any two adjacent preceding train and following train, a VCPM subsystem sends VC operation plan information respectively to the preceding train and the following train in a fully automatic operation mode. The VC operation plan information includes IDs of to-be-coupled trains, a train model, a designated stop position, a stop sequence, a follow-up operation plan, a coupling command, and an uncoupling command.

Each VOBC of the preceding train and the VOBC of the following train determines whether the VC operation plan information is received. If at least one of the two trains does not receive the coupling command, the two trains continue to operate in the current fully automatic operation mode. After the preceding train enters the station for stop and clears out, the following train can enter the station for stop.

If both the VOBC of the preceding train and the VOBC of the following train receive the coupling command, the VOBCs of the two trains respectively send the VC operation plan information to the CBI device and the ZC. The CBI device and the ZC start their respective processing logics automatically.

Modification of the processing logic of the CBI device is as follows: when the train is entering the station, the CBI arranges an incoming route for the train according to the follow-up operation plan, train position and the incoming route in the interlocking table based on the moving block mode, and sends the arranged incoming route to the ZC. The incoming route in the interlocking table is a fixed arrangement. Since the follow-up operation plans of the two trains are the same, the moving block mode is used for incoming route arrangement, which ensures that the end point of the incoming route of the following train is the same as that of the incoming route of the preceding train, thereby ensuring that the end point of the incoming route of the two trains can be located at the designated stop position corresponding to the same platform.

Modification of the processing logic of the ZC is as follows: when the train is entering the station, the ZC calculates the driving permission according to line engineering data stored by itself, the arranged incoming route of the preceding or following train, and position information of all trains on the governed line. The calculated driving permission includes an end position of driving permission of the preceding train, an end position of driving permission of the following train, and line data between a current position of the following train and the end position of driving permission of the preceding train. The end position of driving permission of the preceding train is the end point of the incoming route of the preceding train. Since the preceding train is between the following train and the end point of the incoming route of the preceding train, the end position of driving permission of the following train cannot pass the preceding train, and as a result, the end position of driving permission of the following train is the rear of the preceding train. The ZC sends the driving permission respectively to the VOBC of the preceding train and the VOBC of the following train, such that the preceding train and the following train can drive into the same platform and stop at the designated position of the operation plan in the fully automatic operation mode.

S2: Each VOBC controls corresponding train on a same line, meeting initial conditions of the VC to form an initial coupling, where initial states of all the trains are a stable platform stop status.

On one hand, it is not safe enough for the train to stop in the operation section, and on the other hand, it also affects the operation of other trains. Therefore, before the VC, the state of the train is set to the stable platform stop state to prevent abnormality during marshaling and cause the danger of driving.

The initial conditions of the VC are specifically as follows.

1) An on-board-on-board coupling plan is consistent with an on-board-coupling system coupling plan. The on-board-on-board coupling plan refers to the VC operation plan information received from the VCPM subsystem that the VOBC of the preceding train and the VOBC of the following train send to each other, and the on-board-coupling-system coupling plan refers to the VC operation plan information sent by the VCPM subsystem respectively to the VOBC of the preceding train and the VOBC of the following train.

2) Both the preceding train and the following train stop at the corresponding designated stop positions.

a. The designated stop position can be a parking garage line of the rolling stock depot or a main line platform.

b. The VOBCs of the two trains send the train IDs and train models to each other and confirm that they are in line with the follow-up operation plan.

c. The VOBCs of the two trains send respective absolute positions to each other to confirm that the train itself and the other train have stopped at the corresponding designated stop position.

3) Both the preceding train and the following train are in the fully automatic operation mode.

4) There is no other train between the preceding train and the following train.

The CBI acquires an occupancy status of each section on the line through axle counting to confirm that there is no occupied section between the sections where the two trains are located, so as to confirm that there is no other train between the two trains.

5) Both the preceding train and the following train are in a dry rail condition.

S3: A process of determining, by the ZC, whether each train in the initial coupling meets formation conditions of the VC according to first coupling train IDs and a first coupling sequence in the initial coupling specifically includes the following sub-steps.

(1) After the preceding train and the following train meet the initial conditions of the VC, the VOBC of the preceding train and the VOBC of the following train each send information that the relevant train has stopped at the designated position to the ATS system, and the information that the relevant train has stopped at the designated position also includes the follow-up operation plan, the train II), and the absolute position of the train.

(2) When the ATS system receives the information that the relevant train has stopped at the designated position, the ATS system sends initial coupling information to the CBI device, the ZC, the VOBC of the preceding train and the VOBC of the following train. The initial coupling information includes the follow-up coupling operation plan, the first coupling train IDs, and the first coupling sequence.

(3) According to the first coupling train IDs and the first coupling sequence of the initial coupling, it is determined whether the preceding train and the following train in the initial coupling meet the formation conditions of the VC, which is specifically as follows.

The VOBCs of the two trains initiate vehicle-vehicle communication with each other, and send the initial coupling information received by themselves and the current positions and IDs of the respective trains to each other.

The VOBC of the preceding train and the VOBC of the following train first compare whether the initial coupling information received by themselves is consistent with the initial coupling information received from the other party, so as to ensure consistency of the coupling information.

It is determined whether vehicle-vehicle coupling information and vehicle-supervision system coupling information are consistent. The vehicle-vehicle coupling information refers to current positions and IDs of respective trains that the VOBC of the preceding train and the VOBC of the following train send to each other, and the vehicle-supervision system coupling information refers to the first coupling train IDs and the first coupling sequence received by the VOBC of the preceding train and the VOBC of the following train from the ATS system, and the IDs and absolute positions of the two trains. It is determined whether the front and rear sequence of the two trains can correspond to the coupling train IDs and coupling sequence in the command, so as to determine whether the current position sequence of the preceding and following trains is consistent with the first coupling train IDs and the first coupling sequence, thus ensuring correctness of the positions of the two trains.

If they are consistent, both the VOBC of the preceding train and the VOBC of the following train confirm that they have the conditions for forming the VC, and the VOBCs of the two trains send a receipt of “reply confirmation message for forming VC” to each other. After the relevant trains acknowledge the receipt, it is transferred to the “VC operation” mode, in which the trains can operate according to the VC plan of the VCPM subsystem to form a first VC.

The VOBCs of the two trains respectively send the first VC information to the ZC and the ATS system. The first VC information includes a second coupling train IDs, a second coupling sequence, and a coupling train model.

The ZC determines whether the first coupling train IDs and the second coupling train IDs, as well as the first coupling sequence and the second coupling sequence, received by itself, are consistent.

If the first coupling train IDs and the second coupling train IDs as well as the first coupling sequence and the second coupling sequence are consistent, the first VC is taken as the final VC, and it is confirmed that all relevant trains have been transferred to the VC mode.

According to the above formation steps of VC, all train coupling on the same line are completed to obtain a final overall VC.

S4: The ZC calculates driving permission of the VC according to line engineering data, an incoming route state of the overall VC, and a position of a leading train in the overall VC. The incoming route state includes an incoming route locking state and an incoming route unlocking state.

The ZC deletes unit train information before the VOBC coupling, and replaces it with overall information of the coupled fleet in the VC mode. The unit train information includes the train ID, train route and train driving permission. Meanwhile, the ZC sends information of “the relevant VOBCs have formed VC as required” to the AS system.

The ZC acquires an occupancy status of each train in the overall VC for each section on the line according to axle counting, and sends the occupancy status to the CBI device. The occupancy status refers to whether the train occupies a certain section on the line or whether the section is occupied. All sections from the section occupied by the leading train to the section occupied by the trailing train are occupied sections of the VC.

It should be noted that during the operation of the trains that have formed the VC, the VOBCs of the two trains keep sending VC_MA (Movement Authority) to each other and confirm the consistency.

The CBI device locks or unlocks the incoming route of the overall VC according to the occupancy status, which is as follows.

After the ATS system confirms that the relevant VOBCs have formed the VC as required, the ACS system updates the content such as the operation diagram according to the VC operation plan, triggers the incoming route information according to the VC operation plan, and sends the incoming route trigger command to the CBI device.

After the CBI device receives the incoming route trigger command, the CBI device locks the incoming route of the overall VC according to the occupancy status.

After the incoming route is cleared, the CBI device automatically unlocks the incoming route in sections.

The CBI device handles the incoming route according to the VC operation plan and feeds back the incoming route handling status to the ATS system, and also sends the incoming route state to the ZC.

The IC calculates the driving permission of VC MA_VC according to the line engineering data, the incoming route state and the position of the leading train in the overall VC, where the incoming route state includes the route locking state and the route unlocking state.

S5: A VOBC of the leading train controls operation of the leading train according to the driving permission of the VC.

Each following train is communicatively connected with its adjacent preceding train in the overall VC.

S6: A VOBC of each following train controls operation of the corresponding following train according to each following train's own driving information and driving information of the adjacent preceding train. Each following train's own driving information includes each following train's own driving speed and each following train's own driving position, and the driving information of the adjacent preceding train includes a speed and position of the preceding train.

It should be noted that the leading train operates according to a first self-emergency braking trigger curve. Each following train operates according to a second self-emergency braking trigger curve. The first self-emergency braking trigger curve is obtained according to an absolute braking distance. The second self-emergency braking trigger curve is obtained according to a relative braking distance, so as to ensure the operation safety of each train in the overall VC. The relative braking distance refers to a braking distance of the following train when a speed of the preceding train is not 0, and the absolute braking distance refers to a braking distance of the following train when a default speed of the preceding train is 0.

The method further includes the following steps after S6.

When the train set in the overall VC stops at a next platform, the leading train sends a control demand command to the CBI device. The control demand command includes demand information of all trains in the overall VC for opening or closing of platform screen doors (PSDs) and train doors. Only the leading train is responsible for communicating with the CBI, so as to prevent the realization effect of the VC affecting the processing of the CBI.

The CBI device opens or closes a rail transit PSD system according to the control demand command, and feeds back a control state of the rail transit PS) system to the leading train.

The leading train sends the control state to each following train.

Each following train opens or closes the PSDs and the train doors according to the state.

In this implementation, by designing the establishment process of VC, real-time communications between trains and between trains and ground are carried out for information exchange and backup with each other, so as to ensure the safe and high-efficiency coupling of trains and rapid degradation in case of operation failure of the coupled fleet. The VOBC is first upgraded to the VC mode and forms a coupled fleet between trains, and then reports the coupling status to ground and central equipment such as the ZC, the CBI device, and the ATS system, thereby improving efficiency of the coupled fleet as formed. The trains and ground equipment communicate with each other, report the status, and carry out information redundancy and backup with each other, which has high security.

Specific examples are used herein to explain the principles and embodiments of the present disclosure. The foregoing description of the embodiments is merely intended to help understand the method of the present disclosure and its core ideas; besides, various modifications may be made by those of ordinary skill in the art to specific embodiments and the scope of application in accordance with the ideas of the present disclosure. In conclusion, the content of the present description shall not be construed as limitations to the present disclosure. 

What is claimed is:
 1. A method for trains to establish a virtual coupling (VC) operation mode, comprising: controlling, by vehicle on-board controllers (VOBCs), corresponding trains on a same line meeting initial conditions of the VC to form an initial coupling, wherein initial states of all the corresponding trains are a stable platform stop status; determining, by a zone controller (ZC), whether each train in the initial coupling meets formation conditions of the VC according to first coupling train IDs and a first coupling sequence in the initial coupling; when trains in the initial coupling meet the formation conditions of the VC, controlling, by the VOBCs meeting the formation conditions of the VC, corresponding trains to form an overall VC; calculating, by the ZC, driving permission of the VC according to line engineering data, an incoming route state of the overall VC, and a position of a leading train in the overall VC, wherein the incoming route state comprises an incoming route locking state and an incoming route unlocking state; controlling, by a VOBC of the leading train, operation of the leading train according to the driving permission of the VC, wherein each following train in the overall VC is communicatively connected with an adjacent preceding train; and controlling, by a VOBC of each following train, operation of the corresponding following train according to each following train's own driving information and driving information of the adjacent preceding train, wherein each following train's own driving information comprises each following train's own driving speed and each following trains own driving position, and the driving information of the adjacent preceding train comprises a speed and position of the adjacent preceding train.
 2. The method for the trains to establish the virtual coupling operation mode according to claim 1, wherein before VOBCs control the corresponding trains on the same line meeting initial conditions of the VC to form the initial coupling, perform processes comprising: controlling, by each VOBC, a corresponding train in an operation state to drive into a same platform for stop, which comprises: for any two adjacent trains including a preceding train and a following train, sending, by a VC plan management (VCPM) subsystem, VC operation plan information to a VOBC of the preceding train and a VOBC of the following train in a fully automatic operation mode, wherein the VC operation plan information comprises IDs of trains to be coupled, a train model, a designated stop position, a stop sequence, a follow-up operation plan, and a coupling command; determining, respectively by the VOBC of the preceding train and the VOBC of the following train, whether the coupling command is received; when both the VOBC of the preceding train and the VOBC of the following train do not receive the coupling command, continuing to control, respectively by the VOBC of the preceding train and the VOBC of the following train, the preceding train and the following train to operate in the fully automatic operation mode; when the preceding train drives into a platform for a stop and clears out, controlling, by the VOBC of the following train, the following train to drive into the same platform for a stop; when both the VOBC of the preceding train and the VOBC of the following train receive the coupling command, calculating, by the ZC, the driving permission according to the line engineering data, an incoming route of the preceding or following train, and positions of all trains on a governed line, wherein the driving permission comprises an end position of driving permission of the preceding train, an end position of driving permission of the following train, and line data between a current position of the following train and the end position of driving permission of the preceding train; and controlling, by the VOBC of the preceding train and the VOBC of the following train, the preceding train and the following train to drive into designated stop positions on the same platform for a stop in the fully automatic operation mode according to the driving permission.
 3. The method for the trains to establish the virtual coupling operation mode according to claim 2, wherein the incoming route of the preceding or following train is obtained by a computer-based interlocking (CBI) device based on a moving block mode according to the VC operation plan information, the position of the preceding or following train and an interlocking table, wherein an end point of the incoming route of the following train is identical to an end point of the incoming route of the preceding train.
 4. The method for the trains to establish the virtual coupling operation mode according to claim 2, wherein the initial conditions of the VC comprise: an on-board-on-board coupling plan that is consistent with an on-board-coupling system coupling plan, wherein the on-board-on-board coupling plan refers to the VC operation plan information received from the VCPM subsystem that the VOBC of the preceding train and the VOBC of the following train send to each other, and the on-board-coupling system coupling plan refers to the VC operation plan information sent by the VCPM subsystem respectively to the VOBC of the preceding train and the VOBC of the following train; both the preceding train and the following train stop at the corresponding designated stop positions; both the preceding train and the following train are in the fully automatic operation mode; there is no other train between the preceding train and the following train; and both the preceding train and the following train are in a dry rail condition.
 5. The method for the trains to establish the virtual coupling operation mode according to claim 2, wherein determining, by the ZC, whether each train in the initial coupling meets the formation conditions of the VC according to the first coupling train IDs and the first coupling sequence in the initial coupling, comprises: determining respectively, by the VOBC of the preceding train and the VOBC of the following train, whether vehicle-vehicle coupling information and vehicle-supervision system coupling information are consistent, wherein the vehicle-vehicle coupling information refers to current positions and IDs of respective trains that the VOBC of the preceding train and the VOBC of the following train send to each other, and the vehicle-supervision system coupling information refers to the first coupling train IDs and the first coupling sequence received by the VOBC of the preceding train and the VOBC of the following train from an automatic train supervision (ATS) system; when the vehicle-vehicle coupling information and the vehicle-supervision system coupling information are consistent, controlling respectively, by the VOBC of the preceding train and the VOBC of the following train, the preceding train and the following train to form a first VC; and determining, by the ZC, whether second coupling train IDs in the first VC and first coupling train IDs are consistent as well as a second coupling sequence in the first VC and a first coupling sequence are consistent; when the second coupling train IDs in the first VC and the first coupling train IDs are consistent as well as the second coupling sequence in the first VC and the first coupling sequence are consistent, taking the first VC as the final overall VC.
 6. The method for the trains to establish the virtual coupling operation mode according to claim 1, after controlling, by the VOBCs meeting the formation conditions of the VC, corresponding trains to form the overall VC, further perform processes comprising: acquiring, by the ZC, an occupancy status of each train in the overall VC on each section of the line, wherein the occupancy status refers to whether the section is occupied; and locking or unlocking, by a computer-based interlocking (CBI) device, an incoming route of the overall VC according to the occupancy status.
 7. The method for the trains to establish the virtual coupling operation mode according to claim 1, wherein the leading train operates according to a first self-emergency braking trigger curve; each following train operates according to a second self-emergency braking trigger curve; the first self-emergency braking trigger curve is obtained according to an absolute braking distance; and the second self-emergency braking trigger curve is obtained according to a relative braking distance.
 8. The method for the trains to establish the virtual coupling operation mode according to claim 1, after the leading train and each following train run to a next station and stop, further perform processes comprising: sending, by the leading train, a control demand command to a CBI device, wherein the control demand command comprises demand information of opening or closing of platform screen doors (PSDs) and train doors for all trains in the overall VC; opening or closing, by the CBI device, a rail transit PSD system according to the control demand command, and feeding back a control state of the rail transit PSD system to the leading train; sending, by the leading train, the control state to each following train; and opening or closing, by each following train, the PSDs and the train doors according to the control state.
 9. The method for the trains to establish the virtual coupling operation mode according to claim 6, wherein locking or unlocking, by the CBI device, the incoming route of the overall VC according to the occupancy status comprises: sending, by an automatic train supervision system, an incoming route trigger command to the CBI device; after the CBI device receives the incoming route trigger command, locking, by the CBI device, the incoming route of the overall VC according to the occupancy status; and after the incoming route is cleared, automatically unlocking, by the CBI device, the incoming route in sections.
 10. The method for the trains to establish the virtual coupling operation mode according to claim 2, wherein before the overall VC is formed, the preceding train and the following train operate in a mode of hitting a hard wall; and after the overall VC is formed, the preceding train and the following train operate in a mode of hitting a soft wall. 